1. Field of the Invention
The present invention relates to improved aqueous compositions for the treatment of alfalfa and to the process whereby said compositions are applied to alfalfa at cutting to reduce the time required for drying.
2. Description of the Prior Art
Alfalfa is widely grown throughout the United States for hay and forage. It is also cultivated in Europe and Australia where it is known as lucerne. To reduce the length of time cut alfalfa is exposed to the elements and minimize the amount of handling during harvesting, mechanical and chemical treatment methods, or a combination thereof, are used to speed the drying process. By reducing the time cut alfalfa is exposed to the elements, a better colored dried product is obtained and the risk of damage from rain is proportionately reduced. Rain falling on a cut crop leaches out soluble nutrients and, in extreme cases, can lead to mildew or rotting. Reducing the amount of handling during harvesting, decreases the loss of dry matter--which using conventional harvesting procedures is estimated to be as high as 30 percent, and yields a product having higher nutritive value.
Recent work with chemical conditioners has been primarily directed to the use of aqueous potassium carbonate solutions. Treatment with aqueous potassium carbonate solutions has been shown to effectively reduce the drying time of alfalfa and other grasses under a variety of laboratory and field drying conditions. Tullberg and Angus, J. Agric. Sci., Camb, 91, 551-556 (1978), reported that the drying rate of fully exposed individual alfalfa plants was substantially increased by brief immersion in 0.18 M potassium carbonate solution. Wieghart, Thomas, and Tesar (J. Anim. Sci., 51(1), 1-9(1980)) reported significant improvement in the drying rate of cut alfalfa treated in the lab with aqueous solutions containing mixed methyl esters of long chain fatty acids and a surfactant with or without potassium carbonate. Similar improvement in the drying rate of alfalfa in the field was reported by Wieghart, Thomas, Tesar, and Hansen in Crop Sci., 23, 225-229 (1983) using solutions of potassium carbonate alone and in combination with methyl esters of fatty acids and emulsifier.
While significant reduction in the drying time of alfalfa can be obtained using the aforementioned aqueous alkaline methyl ester solutions, there are certain deterrents to the use of such chemical treatments. Foremost in this regard is the cost of the treatment chemicals. Also, aqueous solutions of potassium carbonate are mildly alkaline and attack/corrode the painted metal surfaces of the harvesting machinery. It would be highly advantageous if less costly alkaline treatment solutions were available which were equally or more effective than the heretofore known products. It would be even more advantageous if useful dispersions of these alkaline solutions could be obtained without the use of external emulsifying aids and if the alkaline solutions were less corrosive to the painted metal surfaces of farm machinery.